Safety chaing locking means for a door



April 30, 1963 D. B. NISENBAUM ETAL 3,087,751

SAFETY cum: LOCKING MEANS FOR A DOOR Filed Jan. 23, 1961 INVENTORS DANIEL B. NISENBAUM LUCILE N. NISENBAUM United States Patent cc.

3,087,751 SAFETY CHAIN LOCKING MEANS FOR A DGOR Daniel B. Nisenbaum and Lucile N. Nisenbaum, both of 1525 Curtis Ave., Manhattan Beach, Calif. Filed Jan. 23, 1961, Ser. No. 84,243 1 Claim. (Cl. 292-464) The present invention consists of a locking night latch comprising a safety chain effectively interconnecting a door and a door frame for limited opening movement and including controllably overridable locking or stop means for normally preventing disconnection of the chain means from the interconnected relationship between the door frame and the door-particularly for preventing this disconnection by unauthorized persons such as a small child within the room or a would-be intruder standing outside of the partially open door.

In connection with the above, it should be noted that conventional prior art safety chains or night latch chains for doors can very often be effectively opened by a person standing outside of the partially open door. This is also true of a small child standing within the room. This has been so in connection with prior art safety chains or night latch chains because they conventionally include two slidably interconnected fastening elements which can be very easily disengaged. For example, a person standing outside of a partially open door may reach in with his hand or with a tool or implement of some sort and merely lift up on the safety chain which will frequently cause the slidable end fastening element attached thereto to slide upwardly and become disengaged from the corresponding mating fastening element fastened to the inside of the door, thus effectively disconnecting the safety chain or night latch from the outside.

Furthermore, a small child standing within the room can very often disengage the slidable fastening element at the end of the chain from the fixed mating fastening element carried by the door by either pushing his hand up wardly thereagainst or by holding some auxiliary longitudinal object in his hand and pushing upwardly against the slidable fastening element.

The novel controllably overridable locking means or stop means comprising a part of the novel safety chain locking means of the present invention completely prevents this type of unauthorized disengagement of the slidable engagement insert means carried by the end of the chain from fully engaged and locked position within the slidable engagement receiving means carried by the inside edge surface of the door. This will effectively prevent an intruder standing outside of the partially open door from unlocking the night latch and entering and will also, in the vast majority of cases, prevent the small child from unlocking it from the inside and thereby getting out of the house, when he is not supposed to do so.

It is an object of the present invention to provide an improved locking means for a door night latch of the safety chain type referred to above, which will effectively prevent opening of the door by unauthorized persons and which is of extremely simple, cheap, foolproof construction such as to be conducive to widespread use thereof.

Further objects are implicit in the detailed description which follows hereinafter and will be apparent to persons skilled in the art after a careful study thereof.

For the purpose of clarifying the nature of the present invention, one exemplary embodiment is illustrated in the 3,087,751 Patented Apr. 30, 1963 hereinbelow-described figures of the accompanying single drawing sheet and is described in detail hereinafter.

FIG. 1 is a fragmentary, small-scale, view showing one exemplary embodiment of the present invention carried by a door frame and in locked relationship with respect to a door.

FIG. 2 is an oblique exploded view of the entire apparatus of the present invention, with certain portions of the chain and with the fastening means removed for drawing simplification reasons.

FIG. 3 is a fragmentary vertical sectional view taken in the direction of the arrows 33 of FIG. 1 and illustrates the locked relationship of the apparatus in somewhat larger scale than FIG. 1.

FIG. 4 is a view similar to FIG. 3 but illustrates the apparatus after the controllably overridable locking or stop means has been manually depressed into unlocked relationship which will allow the apparatus to be unlocked.

FIG. 5 is a fragmentary sectional view of the slidable engagement insert means taken in the direction of the arrows 55 of FIG. 2.

FIG. 6 is a sectional view taken in the direction of the arrows 6-6 of FIG. 2.

FIG. 7 is a sectional view taken in the direction of the arrows 7--7 of FIG. 2.

FIG. 8 is a fragmentary sectional view taken in the direction of the arrows 88 of FIG. 2. FIG. 9 is another fragmentary sectional view of the slidable engagement insert means taken in the direction of the arrows 9--9 of FIG. 2. Referring to the figures for exemplary purposes, one illustrative embodiment of the invention takes a typical exemplary form wherein it includes an improved longitudinal safety chain, such as is indicated generally at 10, provided at one end with means, such as is indicated generally at 11, for firmly fastening it to some fixed ob ject adjacent to the movable edge of a door such as is indicated at 12. In the specific example illustrated, said fixed object carrying the fastening means indicated generally at 11 takes the form of a portion of a door frame indicated at 13, and the fastening means 11 takes the form of a plate 14 having a rearwardly directed edge flange 15 and a receiving cutout 16 and being efiectively firmly fastened to the door frame portion 13 by a plurality of fastening screws 17 in a manner such that the cutout 16 is spaced from the surface of the door frame 13 lying therebehind whereby to provide a receiver for receiving and storing in a non-use position a slidable engagement insert means 18 fastened to the other end of the chain 10.

The apparatus also includes base means, indicated generally at 19, which takes the form of a plate 20 having a rearwardly directed edge flange 21 adapted to rest at opposite ends against the spacers S, which rest against the inner surface of the door edge 12, and adapted to be maintained in firm engagement therewith by fastening means comprising the plurality of spaced screws 22.

The base means 19 is provided with vertically longi tudinally arranged slidable engagement receiving means, indicated generally at 23, and comprising an enlarged hole 24 at the top held in outwardly spaced relationship with respect to the front of the inside surface of the door edge 12 and which has extending downwardly therefrom a somewhat narrower vertical longitudinal slot 25 which 3 is similarly spaced from the front of the inside surface of the door edge 12.

In the specific example illustrated, the slidable engagement insert means 18 carried by the door end of the chain comprises a base plate 26 carrying on its inner surface a slot follower member 27 having similar outwardly flanged lip portions 28 spaced inwardly from the base portion 26 and adapted to be inserted through the hole 24 and then to be moved slidably downwardly into a position lying behind the edges of the slot 25 whereby to be firmly locked against outward displacement with respect thereto.

In the specific example illustrated, the device includes controllably overridable locking or stop means, such as is indicated generally at 29, which, in the specific example illustrated, comprises a spring member 30 which is resiliently mounted at 31 between the plate 20 and the spacers S and which extends across the slot 25 so as to effectively comprise a resiliently mounted intervening bridge member having an upwardly extending projecting or humped portion 32 lying directly in the slot 25 Whereby to normally prevent slidable passage of the slidable engagement insert means 18 either above or below said controllably overridable stop or locking means 29 except when the digitally operable projecting end portion 33 thereof, which extends outwardly through a very small aperture 34 in the plate 20, is controllably depressed while the slidable engagement insert means 18 is simultaneously slidably moved thereby.

The arrangement is such that when the slidable engagement insert means 18 is below the controllably overridable stop or locking means 29 in the manner shown in FIG. 1, it is virtually impossible for an unauthorized person standing outside of the door to disengage the slidable engagement insert means 18 from the slidable engagement receiving means 23 by merely applying upward force to the chain 10. Furthermore, the disengaging operation requires the controlled depression of the actuating end 33 while the slidable engagement insert means 18 is slidably moved thereby, and this is normally impossible of accomplishment by a small child who is reaching upwardly with the fingertips of one hand or with an accessory item adapted to effectively give him a longer reach. Therefore, the novel locking arrangement for effectively preventing unauthorized disengagement of the slidable engagement insetr means 18 and the slidable engagement receiving means 23 is effective for the purposes of the present invention.

Furthermore, it should be noted that the apparatus of the present invention is not limited to operating in a vertically slidable manner or with the two elements 11 and 19 horizontally related. These may be placed in any desired relationship between a fixed member adjacent to the edge of a moving member, either at the side, at the top, or elsewhere, as desired. It will be noted that the arrangement is such that the door can be opened to a small degree as allowed by the length of a chain which will allow ventilation and also allow a person inside of the door to communicate with a person standing outside of a door; yet the arrangement is such that the outside person cannot enter while a small child, or the like, inside the door cannot leave unless an authorized person, such as the childs mother, desires the child to do so and effectively disengages the apparatus of the present invention.

It should be noted that the use of the word door throughout this application is to be construed broadly and is not intended to be limited only to a conventional door used for entering or leaving a room, but is intended to mean any movable member which may normally close an opening or which can be controllably moved so as to effectively open same. This might comprise what is conventionally known as a door, a window, or a variety of similar structures, and the word door is to be so construed.

It should also be noted that the present invention is not limited to using a safety chain, but may employ various other safety tensile members in lieu of the chain in certain forms of the invention.

It should be understood that, if desired, the spacers S may be eliminated. In such case, the edge flanges 21 may be increased in depth and the bridge member carrying the humped portion 32 may normally extend forwardly from the plane of the base portions of the spring 30 which lie in contact with the outer surface of the door 12. In other words, if the spring is so bent that the intervening bridge member bearing the projecting or humped portion 32 normally extends outwardly into the slot 25 while base portions of the spring 30 lie behind the plane of said bridge member and against the door 12, then the spacers S may be eliminated entirely by merely extending the side flanges 21 rearwardly to a depth sufficient to allow the intervening bridge member carrying the projecting or humped portion 32 to be rearwardly deflected completely out of the slot 25 in a manner similar to the showing of FIG. 4 (although base portions of the spring 30 would be resting against the front of the door 12 in this form).

It should be understood that this form of the invention is fully equivalent to the form including the spacers as shown in FIGS. 1-9 and is intended to be included and comprehended within the scope of the present invention.

It should be understood that the use of the expression resiliently mounted, with reference to the spring, is intended to be construed broadly and merely means that the intervening bridge member carrying the humped portion 32 is so mounted as to be capable of resilient inward deflection out of the slot 25, when desired.

It should be understood that the figures and the specific description thereof set forth in this application are for the purpose of illustrating the present invention and are not to be construed as limiting the present invention to the precise and detailed specific structure shown in the figures and specifically described hereinbefore. Rather, the real invention is intended to include substantially equivalent constructions embodying the basic teachings and inventive concept of the present invention.

We claim:

An improved safety chain locking means for a door, comprising: an improved longitudinal safety chain provided with means at one end for firmly fastening it to the inside of a door frame adjacent to the pivotally movable edge of a door, and provided with slidable engagement insert means at the other end; base means provided with fastening means for rigidly fastening said base means to the inside surface of the pivotally movable edge of a door and provided with longitudinally arranged slidable engagement receiving means adapted to vertically downwardly slidably receive and firmly hold said slidable engagement insert means for preventing the door from being opened with respect to the door frame beyond a predetermined distance; and controllably overridable stop means maintaining said slidable engagement insert means in fully engaged and locked position within the slidable engagement receiving means, said controllably overridable stop means comprising a spring member peripherally mounted inside of said base means for forcible retention therein when said fastening means rigidly fastens said base means to said inside surface of said pivotally movable edge of said door, said spring member being provided with a cantilever deflection portion extending from one end thereof along the inside of one peripheral side portion of said base means to a position between opposite ends thereof, and there being provided with a transversely directed portion comprising an intervening bridge member having an upwardly extending projecting humped portion normally lying directly in said longitudinally arranged slidable engagement receiving means in the path of Iongitudinal travel of said slidable engagement insert means into and out of said slidable engagement receiving means for longitudinal abutting contact with one end of said slidable engagement insert means, said intervening bridge member having a free transverse end provided with a forwardly and outwardly projecting digitally operable terminal actuation portion extending outwardly and forwardly beyond said base means for digital actuation to depress said intervening bridge member and said projecting humped portion thereof out of the longitudinal path of travel of said slidable engagement insert means, said References Cited in the file of this patent UNITED STATES PATENTS 1,492,030 Grah Apr. 29, 1924 1,799,258 Shaw Apr. 7, 1931 2,867,468 Bugge Ian. 6, 1959 

